1. Field of Invention
The invention relates to a scheduling system for assisting process planning, such as an operational plan of a production process, into which is introduced by use of a computer a visual programming method. The invention is concerned with a system for representation by replacing an operation of order rows for selecting or rearranging a plurality of input elements with a rearrangement of block images on a two-dimensional image field.
2. Description of the Prior Art
Due to the rapid changes and various demands of the market, the scheduling operation of a plant becomes one of the important factors for determining productivity. It is desired to rapidly prepare a practical plan for operating the plant in response to the changing demands of the market.
The conventional operational plan of a plant depends on the experience and ability of the individual human scheduler. Thus, there are significant differences in various operational plans according to the individual preparing and carrying out such plans. Also, with human implemented operational plans, errors occur frequently. Furthermore, such conventional methods incur high costs. Also, it is desired that production be changed quickly to fullfil rapidly changing market conditions. For this reason, the cycle of change or modification of equipment is becoming shorter and the same equipment is desired to be used for a plurality of applications. When the plant and process are increasingly complicated, the ability of human operators to adapt has certain limitations and the scheduling which is prepared and implemented by humans becomes increasing difficult.
On the other hand, although various types of factory information have been gathered, developed and processed by computers, it is difficult to perform standardization and automation of the preparation of operational plans. Thus, unification of information is hindered. Where the operator must prepare an operational plan using a computer system, there are difficulties involved. The operator must prepare the required software. But, computer programming requires a certain amount of professional skill and experience, which are not always available in the concerned human operator. It is not always easy for the human operator to prepare the computer program software required to carry out an operational plan. Also, no programming method for scheduling, which is easy to prepare, now exists in the art.